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remzibi

A poor man's OSD

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Hello , I think I am in right place . Lastly I start to play with FPV so it is I really like .

I like to show the small OSD project I made just within 2 weeks when I got the max7456 osd chips as samples , all in free time .

Here is the road test I did few days ago:

Now the software is more improved and working well , still on development , but present version is fully working now .

All info is on the sky area as I think that earth is much more important to view .

As main uPC is atmel mega16 - there is no problem to use mega168 but as mega32 is pin compatibile for any future use , it probably remain mega16 as main .

All soft was wrote in bascom because of very fast coding , easy debuging .

I am still waiting for miniature GPS module - as for now I use a big car module just for testing purpses .

Looks like the max OSD chip is very nice and easy to use for .

All project story with some history pictures and schematics/board propsal are there - http://rc-cam.info/viewtopic.php?t=39

- is not english forum but i hope that pictures are speak well for everyone .

Edited by remzibi

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Many thanks for posting, I saw those chips a while back and was tempted to have a play with them but other projects got in the way. Please continue to share this project, I would like to know more about it.

Terry

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Today i've got a small , miniature GPS module , it was working at once after conection , so theory meets with practice :) . I had to rebuild baud rate autodetect procedure - as it was detected 4800 and indeed was 9600 , small bug :) (there was only that two speeds) - now all autodetection function is rewriten and ultimate , works now perfect in full range of baud rate speeds from 4800 till 115200 (at least in theory:) ).

All system working now with any GPS units with any boud rate and any update frequency 1Hz till 5Hz , also it not need to made any additional config of GPS data stream - it must have any stream but must included both GPGGA and GPRMC .

Later todo is play with MTK GPS modules and their comands for stream and data config . I hope to improve frequency by that .

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I never thought about using them in a vehicle like that. Seems like a great secondary application for a traveler or RVer using wireless side or rear view cameras. Now, add to todo list....

Find and figure out how to calibrate a gas flow sensor.......

Figure out how to reverse the scan on small monitors or within the AV unit.....

Make & sell to RVers to help pay for filling the gas tank.......

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Has anyone else used these to good effect ?

I'm using the MAX7456. Like the retired STV5730A, it is relatively easy to use. As a bonus, it has many cool features that are quite handy.

BTW, Eagle Tree is planning on selling a variant of their OSD Expander Board that will be a generic version for custom projects. Something like it would make it much easier to create an OSD project. But, it seems to have been delayed so it is hard to say if and when it will happen. Frankly, if they don't do it, I will. :)

remzibi, looks like a fun project. Please keep us updated with progress reports.

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An OSD that is easy to interface with a PIC would be great, I did have one that used the STV5730A from Black Box (not the same black box as most of you know) but it came on a huge board which made it hard a pain.

Terry

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I'm using the MAX7456. Like the retired STV5730A, it is relatively easy to use . As a bonus, it has many cool features that are quite handy.

Indeed that chip is very nice and easy to use .

BTW, Eagle Tree is planning on selling a variant of their ....., it seems to have been delayed so it is hard to say if and when it will happen. Frankly, if they don't do it, I will. :)

Yes , exactly - they talking for quite long time about that , it is from my conversation on rcgroups .

Finally I was tired to wait for them , and just got my own samples and made the OSD project . Chip is very cute for use with any uPC (PIC, atmel, motorola etc.) as it working via standart SPI bus , whatever software or hardware port , in both cases work well .

remzibi, looks like a fun project. Please keep us updated with progress reports.

Thx , I will write about any news . All relases for dowloads are on that linked forum in first post .

Now I am looking for any manufacturer for cheap doublesided PCP made , any recomendations ?.

The other thing , for increase grafics abilitys , we need a very handy program for characters redefine , the factory program needs factory evaluation board - unfortunate the UART transmition protocol is unknown :( . If anyone have any info about that - let me know - I will try to write small firmware for any uPC for characters and grafics redefinition .

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The other thing , for increase graphics abilities , we need a very handy program for characters redefine

Yes, that would be grand.

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The Black Stork OSD use the MAX chip too. I had to install one for someone, and apart from a few WTFs (incomplete doc, no technical specs given especially about voltage range, wrong labels, utterly stupid "dual power source" from both the flight pack and video battery) this thing is pretty cool for the price.

But it's apparently designed only for people using 3s packs for both video and plane, and that's not mentioned. They offer an "adapter" for 5V cameras and RXs (a DE-SW050 on a board with connectors), but if I hadn't started by removing the shrinkwrap and inspecting the circuit I'd have fried all the video equipment twice.

The aircraft is powered by a 4s battery, which is no problem for the measurement circuitry, but as they take power from both the video and flight pack through 2 diodes (that's not clearly mentioned either), the video gear would have ended receiving 4s.

I also needed to bypass the onboard Vreg so I could use a 4-cell NiMH as all the video gear was 5V. Would have been stupid to use a 3s pack as intended, and requiring that step-down switcher to power everything. Especially knowing that the 3s pack would never have been used with the 4s flight pack ;)

So I just removed the diode coming from the flight pack and bypassed the onboard Vreg. Took me all of 4 hours to install that thing, 1 of which because the labels for the OSD's plugs are swapped... I figured it out by looking at the PCB traces in the end...

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At last , the board project is ready .

23x43mm , small - isn't it ? :) . I hope to manufacture some such small prototypes and test it at least in air .

There are ISP signals outed on pads and all ADC for possible future use .

Uart also can be used for any software updates using any com interface or mobile phone USB cables , bootloader will be preprogramed .

t_m16_f_134.png

So far so good :) .

In home project forum was huge talk about show the posision deg or not in case when model escaping .

Finally , two versions of software ready , with showed position and without . However now the new work is in progress - software for user-configurable layout - with user-cofigurable software on PC .

Edited by remzibi

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The boards are ordered at last .

Meanwhile , using max232 interfeace prepared to play with GPS receiver (it have MTK chipset) and using miniGPS 141 I was able to configure the receiver for any baud rate (here 38400) , 5Hz fix update and 5Hz string update of GGA , MRC and VTG , GSA and GSV at 1Hz , pictures are there http://rc-cam.info/viewtopic.php?t=39&start=125 .

That small evill GPS receiver I start to like more than before .

t_sat_mtk_ok_188.jpg

There is also ready bootloader (flash and eeprom) for OSD unit - working great - any sotware update is possible very quick and very easy from any PC , as hardware can be used any COM interfeace (ex.max232) or COM emulation on USB hardware , using 34800 boud rate is only 3 seconds for mega16 programing - really greate , I was surprised of that :) (why I didn't tryed bootloaders before ?).

After configuration GPS receiver for warious speed I had opportunity to test OSD software - it is detecting and working exelent till 57600 baude rate and with any fixupdate frequency 1-5Hz - once more the theory meet the practice :) .

Finnaly I am waiting for boards and pray they have no errors in project , I checked them for possible errors dozen times - by is good to little pray :) .

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Finally I have ordered boards , that how looks like almost assembled 3 units (still waiting for some missing parts including USB to PC connection ) .

s6300667ri5.th.jpgthpix.gif

s6300668kr9.th.jpg

Soft and bootloader is compiled now for 16MHz so 4 mips more counting power from early version 12MHz added , everything works great till now .

I hope that soon first tests in the air will be posssible , a lot beta testers are ready to do that :) already .

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All soft was wrote in bascom because of very fast coding , easy debuging .

Hi,

I would be curious to see the Bascom code.

Is it made available somewhere?

Cheers

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Hi,

I would be curious to see the Bascom code.

Is it made available somewhere?

Cheers

I would also be curious on how you used Bascom to control the chip. I'm trying to build a scale overlay for a backup camera (see photo) and would like to use this chip. Is it possible for us to see the Bascome code

post-5116-1224701338_thumb.jpg

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I would also be curious on how you used Bascom to control the chip. I'm trying to build a scale overlay for a backup camera (see photo) and would like to use this chip. Is it possible for us to see the Bascome code

When I finish hardware (about week) - I will back to software then we sure will talk about details of chip controling - indeed it is very easy and take not much memory space . In my project all chip controling functions ale less than 2kb .

Yesterday I put first 3 units OSD modules to work . What I was surprised is picture quality much better then in prototype - probably in prototype cable lenght was playing role .

As GPS I find that one - 16x16mm with MTK chipset , working very nice .

It have not backup battery but geting fix very quicly .

Do not look at date - camera had reset :) .

t_gps_124.jpg

t_gps_opis_129.jpg

As interfeace with PC all friends are talking about USB key - they doesnt want any com solution with max232 or similar - so finally I provide one .

It is universal USB-uart (TTL) bridge , working very well with any terminals and bootloaders - in fact should work also with other uPC OSD units but not for 34EUR(like blackstork) only less than half of that cost .

It is how it looks like :

t_usb_471.jpg

The other hardware version a bit more expensive is also ready working with Vista (if anyone use that .....) , after some playing with PID and VID no drivers for Vista is needed - it instaling that USB bridge from windows update .

This USB key also can be connected with GPS modules for testing and configurating puroses , cooperate with visual GPS or miniGPS from MTK and other software very well till now .

t_gps_usb_366.jpg

Bootloader I choose MegaLoad - working as charm , takes only 512kb from memeory for reprograming flash and EEPROM - just compare with Arduino 2kb of memory fot the same job .

I had also questions why I choose atmel AVR for this project - it is really long talk about that - but I found this small video explaing in short my decision :

http://www.youtube.com/watch?v=wT4MbenQ3RE

As the units at least works - soon fist test from air . I want to check how will they go with ESC glitches , and video TX in air practice .

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What's that tiny GPS module? I like!

I found this small video explaing in short my decision :

http://www.youtube.com/watch?v=wT4MbenQ3RE

I wouldn't consider such a "comparison" to be of any value... Taking the same code, feeding it to 2 different compilers and running it on 2 different devices will run, but you'll be benchmarking the compiler as much (or more?) as the device itself. Especially as the guy doesn't even say what he used.

Edited by Kilrah

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What's that tiny GPS module? I like!

It is of Taiwan manufacturer named GlobalTop , module I bought here in Poland from his resseler . Module have MTK chip and using miniGPS is fully configurable from 4800 to 57600 baud rate , also position update till 1-5Hz and what strings will out and what frequency each one . If backap battery is used all config can be hold in memory , now all config reseting after power down . When I query flash store attempts is 0 , so save settings to flash is immpossible .

There is another modules (25x25mm but tiny and light) of the same manufacturer , I had to test and there is possible configuration settings store in flash (7 attempts) , so backap battery is not nedded .

I wouldn't consider such a "comparison" to be of any value...

A agree , it is just for some kind of short of most siplificed-funny explanation , in real there are many more reasons mostly considered personally by me .

All microcontrolers are great and for some are better this for other others - all depends from designer who is using this or other for certain specific reasons .

Edited by remzibi

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OK, looks like the manufacturer had a website but the domain expired a couple of days ago, no information to be found anymore. I have some 25x12mm MTK GPS modules on the way, but that one is really the smallest I've seen so far!

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Oh, works again. This page was listed as domain for sale yesterday. I guess they forgot to renew their domain name subscription ;)

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I think the the primary goal is aquired , the cheap OSD unit hardware platform .

The hardware OSD platform for 120$ including OSD unit , GPS receiver (16x16mm) and USB key for connection to PC (software update , GPS checking and mny more usage ont only for this OSD) .

First sets are on the way for betatesters already . (price is counted in relation USD/EUR so can minimally flow)

This is the pictures how it looks like :

opisci5.jpg

w2048.png

All software for it can be dowloaded fom there :

http://rc-cam.info/viewtopic.php?t=131

bootloader .hex and PC software (it is free solution) and two versions of working OSD software . You can belive or not - but software for that device was wrote at begining in very short time - all rest time was taken by hardware part of device , now when the hardware is ready I hope can be back to software part , a long time for corrections forward .

If anyone want write his own software , schema is also there , any other bootloader can be also used .

If there will be any interest from english speaking peoples - I made english version - now most you guess from pictures only .

However - the cheapper price is also possible ,

- if you do not need GPS receiver - minus 25$ from price

- not need USB key - minus 6$

- if you have the samples of max7456 in drower (3-5psc) and if you send them to me (registerd letter) the price - minus 20$ .

- do you have electronic experience (advanced experience) and tools ? - you can have the printed board for 7$ and made the device by your self

For admin - if that message with prices ect. are not allowed here - please before delete let me know - I will edit that post .

If anyone interested , feel free to write me at PM if any questions .

Edited by remzibi

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I think the the primary goal is aquired , the cheap OSD unit hardware platform .

The hardware OSD platform for 120$ including OSD unit , GPS receiver (16x16mm) and USB key for connection to PC (software update , GPS checking and mny more usage ont only for this OSD) .

First sets are on the way for betatesters already . (price is counted in relation USD/EUR so can minimally flow)

This is the pictures how it looks like :

opisci5.jpg

w2048.png

All software for it can be dowloaded fom there :

http://rc-cam.info/viewtopic.php?t=131

bootloader .hex and PC software (it is free solution) and two versions of working OSD software . You can belive or not - but software for that device was wrote at begining in very short time - all rest time was taken by hardware part of device , now when the hardware is ready I hope can be back to software part , a long time for corrections forward .

If anyone want write his own software , schema is also there , any other bootloader can be also used .

If there will be any interest from english speaking peoples - I made english version - now most you guess from pictures only .

However - the cheapper price is also possible ,

- if you do not need GPS receiver - minus 25$ from price

- not need USB key - minus 6$

- if you have the samples of max7456 in drower (3-5psc) and if you send them to me (registerd letter) the price - minus 20$ .

- do you have electronic experience (advanced experience) and tools ? - you can have the printed board for 7$ and made the device by your self

For admin - if that message with prices ect. are not allowed here - please before delete let me know - I will edit that post .

If anyone interested , feel free to write me at PM if any questions .

Is it possible to post the Bascom Basic program that shows how to control the max7456?

As I mentioned in an earlier post, I'm trying to make a backup camera overlay and I think your program will help me alot

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